diff --git a/ccs.wdl b/ccs.wdl
index bcebefe948b4a1f1c01bf76c6c2b764ea2cdd8d4..5d9887bfcfa21b0d5e5e386f2ac33fcb55e90df6 100644
--- a/ccs.wdl
+++ b/ccs.wdl
@@ -81,7 +81,6 @@ task CCS {
         logLevel: {description: "Set log level. Valid choices: (TRACE, DEBUG, INFO, WARN, FATAL).", category: "advanced"}
         subreadsFile: {description: "Subreads input file.", category: "required"}
         subreadsIndexFile: {description: "Index for the subreads input file.", category: "required"}
-        outputPrefix: {description: "Output directory path + output file prefix.", category: "advanced"}
         chunkString: {descpription: "Chunk string (e.g. 1/4, 5/5) for CCS.", category: "advanced"}
         outputPrefix: {description: "Output directory path + output file prefix.", category: "required"}
         cores: {description: "The number of cores to be used.", category: "advanced"}